Various weights pop up on ebay from time to time, look at ebay UK also, you have a nice original SME head shell, I can't tell what weight you have on the back, it's cut off in the pic.
I had a Grace F9E in the '80s, Love, love, Loved that cart!! I never had an issue getting proper VTF with my arm. Do you have a gauge? You really can't hurt your Lps too much by tracking heavy, I'm with Mark tho, coins on a beautiful arm makes my skin crawl