Bicycle Mechanics - Any stem options for 1 1/4 threadless fork - Shimmed 1.5, maybe?

I've got a cool old mtb with a 1 1/4 threadless fork that I'm cleaning up. I'd like to keep the original fork, but obviously the stem selection is pretty thin. I was wondering if I could shim a 1.5 stem or maybe an early Headshock stem down. I don't know how much bigger those headshock steerer tubes were, but I'm open to options as long as I can keep the original fork.

What length & angle of stem are you looking for?

Check Santana Cycles. They'll have them.

I don't really know what size I'm going to need yet. The bike is a pretty weird setup, the steerer tube is threaded for the headset and then has an extended part above for the threadless stem to clamp to. I'd like to set it up with a dirtdrop, but I'd need an stem with rise. It looks like a Santana tandem one might be my only chance. I might look at homedepot and see if there is any pipe with the right ID and OD to make a shim for 1.5 since stems are soo much cheaper in that size. Here's the project:

http://img823.imageshack.us/img823/7232/redlineu.jpg (http://img823.imageshack.us/i/redlineu.jpg/)

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You have a conversion from threaded to threadless, It appears,
You can find a different threaded to threadless Quill that is 9/8" at the top,
then the vast assortment of stems made today can be used.

No, the extension is part of the fork. It holds the compression and lockout internals. I'll try to take another pic later today. It's a Redline 20th anniversary frameset with a Browning Aero-tech linkage fork.

R&E in Seattle can probably hook you up with a frame builder to make what ever stem you need.
Tig Steel construction like the rest of the bike.