Weight and balance between the two is very similar. Grip shape is a bit different, but within reasonable parameters given what you want it for. Action for the real thing is obviously different, but that shouldn't matter.
Nice call BTW. I haven't found much on airsoft Hi-Powers.
About the only thing I have found is a company in Taiwan (Tanaka) that makes three models; a MkIII, one they call a military model, and one modeled after the Inglis. Most of the websites I found that sell them are overseas, with a price around $175.00 US. Almost all of them indicated they were out of stock.
The gun is of a gas blow-back design (which is good) but seems to be made almost entirely of ABS plastic.
Specs for one I found indicated the weight at about 20 oz, a length of 7.9 inches with a height of 5.1 inches. It shoots the 6mm plastic bbs.