So, I have been on the search for a 35mm adapter.
I've read a lot about the indian ones on ebay, and "you get what you paid for", but if people are just buying the m2 diy kit, isn't it work paying the extra $50 for them to build it?

I found a new guy, eBay Seller: bsumotivator: Cameras Photo items on eBay.com (http://shop.ebay.com/merchant/bsumotivator)
Can anyone tell me if this is a good price for a DOF adapter, 72mm, for my xha1?
I'm willing to pay the extra $40-$50, more than the m2 diy kit, because it's already assembled.

I dont really feel like spending $1000 for a letus.

Are there any other cheap solutions?
I don't want to build one, because i know i'll somehow mess it up.

Having built the DIY Redrock, or my version thereof, I can offer the following comments:

1. The M2 has a spinning disk ground glass, there is just a comment about their ground glass, but no reference to whether it is spinning or vibrating. Since you are going to the big box, spinning is better than ground glass in my opinion.

2. Achromat: one of the most important parts of the set up is the achromat. Most cameras need an achromat to allow the camera to focus close enough on the ground glass to get the best part of the thrown image... I doesn't sound like one is offered here.

Do NOT buy. Poor diffusion, boxy and ungainly, you're better off investing in quality equipment. At least consider something more midrange...this is built-in-a-garage poor. Your XLH1 will hate it, and you will too.