Sounds sweet, do you have any pictures?
For the cloth you may just need to find a good auto upholstery shop in your area. You could try and find the shop that local dealerships use for installing aftermarket interior accessories (different seat upholstery, sunroofs, cruise contorl, etc.) At least in my area that's the best place to go.
For the plastic levers, they may be the same as any 2-door E30 seat. You could probably find some that will work from used seats or at a junkyard.