Yes, ANY year Beetle transmission between 1969 and 1978 will work, but bear in mind that your 1300 transaxle was designed for 40 hp. Come to think of it.....a 1972 Beetle over here had a 1,600cc engine. Are you sure that's a 1,300??
Most of us have "beefed up" VW transaxles from Rancho Transaxles in Fremont, California to handle power from 85hp to 150hp. You would need a 69-78 "Pro Street" IRS transaxle if you go the 2,109/2,110cc engine route.
https://ranchotransaxles.com/vw-transaxles/
They build them in several stages so they can handle the added horsepower we run. Because of all of the open spaces and the Interstate Highway System here, we often opt to run "Freeway Flyer" transaxles with a 3:88 rear end to keep the engine revs down a little at 70-80mph, but if you plan on mostly country roads and little motorway driving, a stock 4:12 might be ok for you.
I have not heard of JCS for engines, but many of us have engines from CB Performance in California. I happened to build my own, but that is getting rare (unless you're Stan).
http://www.cbperformance.com/T...gines-s/138.htm#2109
The shipping alone to the UK might choke you (I think it might double the overall cost), so wait a bit (you have the time) and ask around about who builds reliable aircooled engines in the UK - I know there are at least 2 or 3 and that might be a better choice. @Ger up in Scotland might know of someone to get in touch with (he'll get a notice of this post).
So, as you can see, we're already spending all of your extra cash for you (and quickly, too!) Take this slowly. It is really easy to waste money (a LOT of money) on the wrong stuff, so let us guide you through all this. Granted, some of our knowledge about where to go for things in the UK might be limited, but, hopefully we'll get a few more Brits on here to help out. Seek out some of the UK VW clubs - they will be a great source of where to go for what.
Gordon The "Speedstah Guy" from around Boston
BTW: I love your brick garage floor!