What about a 355mm G-Claron? Those usually sell for around $500.00 range. However...I do not know how much smaller or ligher weight it is!
EDIT- I just remembered the 360mm Apo-Ronar would be a good replacement for your 14" Artar. It's smaller and lighter than a G-Claron. You see them on Ebay once in awhile mounted in a shutter.