Brougham Dodge 1979 engine

An almost 42 year old motorhome will need a very careful inspection of the total RV. Be careful! And if you are not a mechanic or experienced RVer, get help.

There is a long running thread on Dodge based Motorhomes,a post might get some good answers over there.

Dodge Based RV

I strongly suggest it is a Dodge MB300 chassis. 360 engine with 2 bbl carb. I had several similar vintage class c campers.
PM if you want.

Very few 1979 motorhomes are worth buying. Not many make it to that age with owners who keep up with roof and window maintenance to prevent water leaks from rotting the body. If you are not knowledgeable about RVs, spending money on a qualified RV inspector may save you money and aggravation. Another issue with RVs that old is that while mechanical parts can still be found, it's unlikely a parts store will have them on the shelf, often necessitating several days wait until it can be shipped in.

Not to sound harsh, but if you have to ask these questions, an antique vehicle the the "owner" cant get running with a $20 part, 20 minute fix (did you know that?) with a leaky box on the back full of other things that will be or are broken is not a wise purchase.
Unless you're homeless, then it should be about the cheapest rolling shelter you can buy short of a tent and a wheelbarrow and generally the 360/727 drivetrain is reliable, provided it's actually in good operational condition.

I would be skeptical about the bad fuel pump. Rig may not be able to run, you can't road test it. An old $13K "bargain" rig cost us some 12K more in repairs to get it usable long ago before we knew what we were doing. Replacing roof AC units, water heaters, fridges, RV generators, converter chargers, fresh water pumps, and house batteries plus 6 correct type quality tires and brakes, awning and suspension can raise the cost of a "cheap" old tired shabby rig to where it exceeds cost of a much newer and overall better, safer, fully usable rig. You may not be able to buy discontinued 8.00 X 16.5 tires and need to replace wheels and use new radial tires. Water damage is very costly to have fixed.