You have all the pieces there for identification, as Old Doug says it's generic propane gear and is available everywhere on the net or from any decent forklift dealer or parts outlet. Also some propane distributors do installs and repairs. One question though, why would you think it needs any of that stuff? Those components are usually almost totally bulletproof. There are kits available for the convertor for about $20, or the complete unit new on EBAY for about $75, the carb runs around $125 or so, just search on the part number or model there. The fuel lock solenoid and filter are are interchangeable, just get a solenoid valve that matches the battery voltage.
Fuel hose is usually made to length by your local hydraulic hose supplier, or again a decent propane distributor or forklift dealer.
So, what's it doing/not doing that makes you think it needs work on the propane gear?
That's a Continental flathead engine, maybe even a Y112 in a machine that small.
Usually the rating would be 2,500 pounds at 24" load center, sometimes the smaller machines would be rated in closer, but you're probably okay with 1,300 at 32" I'm not suggesting this, but it's fairly common on these older machines to see some yard art additional counterweight metal hanging off the back end to help keep the steer tires in touch with the ground.