I found a bellhousing for those that are looking for a one for a 11" clutch. Its a remake of the original style and its the cheapest one I have found. Its in low stock, so it says, but take a look.
http://www.elcaminostore.com/el-camino-bell-housing-11-style-621-1964-1981.html
Hope this helps.
http://www.elcaminostore.com/el-camino-bell-housing-11-style-621-1964-1981.html
Hope this helps.