I have to say. It seems amazing that it is not a simple matter to determine, but after seeing photos of these other nice sxs's it is hard to say for sure which one it seems more like. What are you refering to as a "cruciform' trigger plate? Are there different pics I could take to help determine what I have?
thanks, Gary
Gary:
Go to your picture No 3 where you have the gun inverted. Note that the forward part of the triggerguard is cruciform(In the shape of a cross) where it's inletted into the bottom of the receiver. This is an uncommon and expensive option so your gun could very well be a Model 53. The one way to find out for sure is to email AYA with the serial # and ask them.
Jim
