Excavator Pin material

I have a Kubopta KX121 that had a WB thumb added to it, I am replacing pins and bushings and bushing the holes in the bucket.
I can't get the replacement pin from the manufacturer so I have decided to make a replacement. I have 4140 annealed shaft that I can use and I have some 4130 that I can make the bushings from.
Could someone make a material recommendation for the pin and bushing material for the bucket.

Thanks, Steve

Excavator Pin material