It is likely a "Flower Car" - carried flowers for high profile funerals. There were a couple of builders back then. You need to finder out the builder to get more info. Back in the day the big three built comercial chasises for builders to use vs. the chop and splice that is done today. As with old cars if you like it and will drive it - buy it. If it is just going to sit in the garage, it may not a good investment.
It will be OK