The machining and finish of the actual trigger block I reckon is a far more costly item,though I would love to see this on a HW springer.
Would a TX block fit a 95 with a shim of some sort (and a re drilling of the lug maybe) or even buttonning the block? The rear of the cylinder would obviously have to be shortened to allow the safety in the trigger block to work.
I'm sure if AA spares were a little more common I'd have actually had a look at this.