Honestly, it isn't worth the effort. It's a 4 amp 4.5 inch grinder. You can buy a new equivalent one for $20 at Harbor Freight, or a much better one for $30.
Harbor Freight buys their top quality tools from the same factories that supply our competitors. We cut out the middleman and pass the savings to you!
www.harborfreight.com
Amazing deals on this 4-1/2In 7Amp Angle Grinder at Harbor Freight. Quality tools & low prices.
www.harborfreight.com
Older Blue Ryobi tools were either US made, or maybe Japanese made.
While there are some cheaper angle grinders of supposedly similar power level, a lot of people liked some of the older Ryobi tools.
I have no clue were to get a replacement pin though, so it might be more trouble yo fix yhan it’s worth.
Craftsman used to rebrand Ryobi stuff in some cases, so that might be another option to look for a replacement part?