All I know is that Brownell's sells an action wrench for the SMLE, and that you should not use something that's not made for an SMLE (either the action 'wrench' or the barrel vise) if you use something rigged up you may risk damaging the receiver, or so I've heard.
http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=25121&title=SHORT%20MAGAZINE%20LEE%20ENFIELD%20RIFLE%20ACTION%20WRENCH%20&%20HEAD
I heard it's a good idea to get an extra bolt and take the extractor out and use that to support the receiver whilst you take out the barrel.
Barrel vise:
http://www.gunbroker.com/Auction/ViewItem.asp?Item=121984695
I don't really know much about taking off SMLE barrels, maybe someone will help you out with some more information in that regard.
If you want to make one of those Jawa zappers, just get a machinist to rig up some bushings, *and the 'barrel' of course, the rest can be common pieces of pipe hold the thing together with set-screws, hey all you are doing is going to get a solid piece in there for the barrel right? the outside diameter for the 'barrel' can be a common od like 1"
Edit: for the pipe, try to get something with a uniform wall thickness, and no seam.