Firstly what computer are you planning to run to control everything? Reason being if you're going to use a stock ECU keep in mind the Crown uses a different type of speed sensor number 2 to control the trans, Kelvin may correct me if I'm wrong but I think that they use a 36 pulse signal to the traction control computer which in turn converts the signal for the TCM. In other words getting it to shift properly can be a bit of a mission. Another option (and I'd have to do a spline count for you once I get everything sorted out) could be to use a Surf transfer case output flange and modified Surf driveshaft (which has the slip joint in the shaft) on the existing trans
But to answer your question the trans is worth anywhere from a slab (carton) of beer to around $300.It pretty much depends what you're prepared to pay and what is agreed upon.
I normally end up throwing the autos out but of late have been giving them to a friend whose been using the cases to make tables out of, Yet the last Crown trans that I had I stripped and kept the main shaft and extension housing.
FYI they're a 23 spline shaft