Not sure you'll find anything in your price range and will struggle with the movement height too.

The ETA2892 and Soprod A-10 are known to be fairly thin and they are 3.6mm.

A cheaper movement (but still probably over budget) would be the Miyota 9015 but that is 3.9mm

 

The Lemania 8810 is 2.95mm, finding a watch with that one, you'll be paying more that 100 just in sales tax.

 

The closest you'll get with that movement is a use or NOS Ebel Type E or 1911 Senior, both of which were made in the late 90's and early 2000's. Look for a reference number that started with 9080... (Ebel's caliber 080 is a Lemania 8810 and the 9 means the watch is steel). The sales tax on that one will be less than $100, but not by that much.

The Lemania 8810 was originally the Longines 990, which I think may still be the thinnest automatic with central seconds and date ever made. It's the only automatic movement in watches that are even remotely affordable that is thinner than 3mm.

Many automatics used in the 60's were not as thin but the watches in which they were use were very thin compared to current watches.

The closest you'll get is an ETA 2892 or Sellita SW300 (or Chinese clone, including the Seagull ST18), which are 3.6mm thick. Finding watches with basically finished ETA or Sellita movements in the several hundred range (used or very deeply discounted) is not impossible, and Seagulls with the ST18 movement (such as their 8mm ultrathin M201s) are in that same price range new. I think that's about as good as it gets for an ultrathin auto.

Now, if you can live with a handwind, there are zillions of vintage handwinds that would be called "ultrathin" today, being 7mm or so in thickness for the overall watch. One inexpensive option is a Favre-Leuba with their caliber 253, which is not hard to find for under a C-note but is hard to find without having a garishly repainted dial or a movement full of corrosion resulting from decades of Mumbai humidity. But there are many others.

Rick "thinking this is a tall order" Denney

 

Skagen makes very thin watches...Oops Quartz My Bad

 

The ETA/Peseux 7001 is a 2.5mm thick handwind movement, but I doubt you'll be able to get them for under $100 per movement.

 

Maybe something vintage? An automatic 60's tissot or Seiko will probably come under $100. Good luck

 

For the record, Zenith Elite auto movement with quick-set date and small seconds is 3.28mm. Out of your price range , like most of the above, it was introduced in 1994 so you may find an old one at an affordable price.

 

b-) Nivrel uses the 8810 quite often and there's one available right now.

 

Mondaine has some great pieces if you can find one on sale.

 

Thank you everyone for your responses.
To be clear, I'm actually just looking for a movement that I can source in bulk.
So I have order quantity working in my favor.

In general I was having a hard time finding a automatic movements under 3mm. The idea is to have a 5-6mm total watch height.

Everyone's thoughts and expertise are greatly appreciated.

Cheers!

 

Have you been able to find movements that meet your specifications? If so which ones have you found?

 

You're either oblivious, or insane. There's a reason watches like Piaget, Blancpain, and Vacheron Constantin (all makers of ultra-thin mechanical watches) cost so much - because the companies spend from hundreds of thousands to millions of dollars in research and development. Designing a thin automatic watch is not an easy feat. To expect to have a movement costing less than $100 per unit fit in a 5-6 millimetre case is, quite frankly, unrealistic insanity. If such a calibre existed, it would be popular and this thread would be solved by now.

 

Seagull has apparently been working on a new microrotor movement, but it is apparently only going to be used in limited quantities in their higher-end line of watches, and will not be available as a stand alone movement.