That is the lesser-known No. 640. The difference does appear to be the standard strap; but also what Myres' competitor Heiser called the 'quick draw belt loop': the leather is cut away at the fold of the belt loop. Lawrence also had two versions of the Threepersons-style holster; one with standard loop, one with quick-draw cutaway. Can't help you on the fitment.

It is from Myres' 'early' period because it's marked 'tex' in the maker's mark; we believe but don't actually know that the early period was before Sam's death in '53. Can't even find a reason for the changeover. One could speculate without even being close, that the new stamp was created when Myres was taken over the first time in '65 by Harlon Webb. But Webb had his own version of the Myres stamp that were used on his saddles.

An excellent condition Myres can sell on a standard auction site for several hundred, on 'real' auction sites for ten times that; have a look through worthpoint.com for that info.

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Red Nichols The Holstorian