any suggestions on changing out cams/upgrading?

You can have your OEM cams welded and reground by Kent Cams in the UK for around 238 GBP.
Otherwise performance cams are very difficult to come by for the RC51 these days.
There was a fellow in New Zealand that was making high quality billet cams for the RC51, but they coat about $1800 for a set and needed your cams for the drive gears.

It really depends on what you are trying to accomplish with the bike. Just throwing hotter cams in there can definitely be a performance improvement, but it depends on where you want more juice.