I'm sorry it's taken me so long to respond...I didn't see your follow-up post.

If they made the drawings I can understand their reluctance to provide them to you. I wouldn't hesitate to ask for something in writing that states that you own the drawings but they retain them. That's one option that will provide you with a little protection. The other option is to hire a draftsman to draw them from your prototype...then you own them and can shop them around for the best production deal.

I went through something similar when I was trying to hire a landscaper. The first one I interviewed I walked him around and explaining exactly what I wanted...they gave it to their architect and brought the plans back. After we went over them I asked for them and they told me No, saying they never give out the plans. I tried to reason with him that if someone won't provide me plans that will allow me to compare apples to apples, I automatically suspect their quote is going to be too far out of line. When I went to 3 other companies, they all willingly provided me with copies of the prints...all 3 were pretty close in cost....about $12,000 less than the guy who wouldn't give me the plans.

If you got the drawings without the dimensions, why not spend a hundred bucks on some micrometers and calipers, measure and put in the dimensions...or take your prototype to the draftsman as mentioned above. Right now in this economy I suspect if you shop the work around, you may find it a lot cheaper...they just want to keep their doors open.
Good luck