According to Google, and Bing, the average prices are around $6.00-$20.00.
From what your description is telling me, your going to be using good quality meat, and spending a lot of time making chili(Chili is a pain to make:P), so, I say $15.00 a dozen.
That times 10 would $150, so I so say go for it.
It is time consuming not costly, sell yours for 1.50 each, fair price.
I steam 40 at a time so that isnt much, alot of fun to do with Kids or the Elderly.
At the local store, the real tamales are 2 for $5. However, there used to be a nice Mexican woman who would come around knocking on doors selling hers at $15 a dozen. My husband used to get those often. Nothing like good authentic Mexican home cooking.
I sell mine @ $12 a dozen and theyre worth way more lol