When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I'd look at going to Stratus, E-One, Pierce, American LaFrance or just do a lot of old fasioned internet searching for used ambulance and fire truck parts. But with a vehicle that old....16 years it may be a difficult piece to find.
Good call I think. It will probably be cheaper than finding a pre-made one, because the few people that will have one will think its worth it weight in gold.