i don`t know what your mechanical skill level is but ,,,you should try soldering it up yourself . All you need is a small handheld propane torch, a wire brush, acid core flux and lead solder ,, Just heat spots up slightly and scrub with wire brush till clean in the spot to fix ,heat again then wipe /pour flux cleaner on surface, then heat just hot enough to melt solder with surface then add lead quickly flow then cool with rag around ( to keep from melting other joints ) ... The only hard part of learning to do it is not over heating it so hot that it melts other joints...
You have to use acid flux and or acid core solder ,,,both if possible.
You can do it ,,, and having a couple radiators laying around you have practice material..
sorry for the semi thread jack..but trust me you can do it..