Oh well, I found the answer myself (D'oh!). I contacted a UK supplier (twistedtime.co.uk) and asked - getting a very rapid respose to the effect that, yes, one can swap with NATO straps: lug size 20 mm.
Couldn't resist adding that, having settled the straps issue, my resistance was futile: one black-dialled Uno 24 with black PVD surround now on order - to be dispatched tomorrow, I'm told! All being well (and assuming I can work out how) some pics should follow soon on a new thread.
p.s. Sorry if I'm talking to myself a bit here!
p.p.s. New posting now up - pics seem to have loaded OK, so all set for proud new owner!
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