Van turns over but won't catch

Hello. I recently purchased a 1987 Dodge B250 Ram Van from a private seller on Craigslist. Before I bought it I drove it to a garage in the sellers hometown to get it looked over. When it was at the garage it had a very hard time starting for them to even bring it into the garage, they jumped it and it ended up working but every time they turned it off they'd have to jump it to start it again.

Then once I purchased it it started fine twice on the way home, I parked it in my driveway, went to start it again later that day and it never started again. It is currently in a garage and they are pretty sure it is the Ignition control module.

My issue is I have the part number from the original dodge dealer that they had on the van but can't find a replacement for it anywhere online.

Can anyone recommend somewhere for me to find this part? The ICM in the car right now has no part number on it thats why I called the dealer.

This van is in beautiful condition and runs like a champ I can't just let it go.

The part number that the dealership had listed on the van was R4379223

Its a 5.2L engine

If you don't mind used you'll find a few of them through this site: http://www.car-part.com

http://www.moparpartswebstore.com/ They showed the part in stock.
I painted you item you showed and google found the part.