There were similar catches used for drawers and cabinets in the '63 and '64 coaches. I had to look for ages before I stubled across some NOS latches on E-Bay - - I purchased them in a small lot and the price averaged out to about $20.00 each. So far as I was able to determine there are no modern equivalents available.
The most difficult to find replacements for (or parts for that matter) are the large variety of the latches that are used on the wardrobe and pantry cabinets in my Overlander - - I dropped out of the bidding on a pair of those when it surpassed $60.00. The catch portion of my locks are fine, but the knobs have disappeared over time.
The actual mechanisms didn't change much between '63 and '64 but the exterior handles did change - - the '64s were smooth with indentations in the center - - the '63s that I have seen had serated edges with a flat front. The '64s appear to be chrome plated while the '63s appeared to be polished aluminum.
Goog luck in your search!
Kevin D. Allen
WBCCI (Lifetime Member)/VAC/Free Wheelers #6359
1964 Overlander International/1999 GMC K2500 Suburban (7400 VORTEC/4.11 Differentials)
1978 Argosy Minuet 6.0 Metre/1975 Cadillac Eldorado Convertible (8.2 Liter V8/2.70 Final Drive)