Thanks for the kind offers guys but I think I might have a solution.
I dug through the kits in my stash and think I found something I can use in a 1/72 Academy P-47 Razorback kit. I had two of these and used one of for the P-47J conversion I did a while back, stuffing the unused sprues into an unused razorback kit so there were 4 1/72nd 500 pounders in there. They are slightly too big around and need some modification on the tail fins, but I think they will be OK. I had found 2 of the same side halves (both with the locator pins) in the spares box that match and must have been from the same kit Razorback kit from years ago, so If I can mate those parts together, I will have 5 of the same type. If I put them all on the same wing, I don't think the slight diameter difference from the 250s I already have will be noticeable.
I started the fin modification and will try to finish them up tonight and post some pictures comparing them to the 250s I already have.