Is this hinge available?

I have a top hinge on a casement window that has a worn/broken wear block (the black piece in this picture) and it comes out of the track when opening. That piece is broken/worn and it appears I will need to buy the entire hinge although I could rivet a new block if they were available.The closest thing I found is Truth Kit p/n 51755 but it has a 10 inch track not on my window. The existing track is in good shape
I cannot locate this hinge assembly anywhere and the dimensions are short arm, Truth p/n 30744 (approx 5.25 inches), long arm Truth p/n 30451 (approx 7.625 inches) and the stationary foot at the end of arm 30744 is Truth p/n 20602. The broken block has no visible part number.
Your help is much appreciated!