Transport carrier from MI to Colorado ?

['68StangGT]

Doing some long term planning here

my wife is giving her somewhat rare car to her son - (a '71 Olds Cutlass SX Convertible)

We live in Mid Mchigan, and he lives just outside of Denver (Arvada) = so roughly 1250 miles.

What do you think it would cost for him to use a car transport service ?

anyone have experience with a particular company ?

Thanks in advance