Truck shop -
http://truckandcarshop.com/
I seriously doubt there are many different manufactures. I'm sure most of the dealers are selling the same product. There were less than 80K first Gen Blazer produced. Probably less than half as many Jimmy's. Factor in how many have met their demise in one way or another, and what is left is a very small market. Not enough for multiple manufactures to make enough money to produce the product.