Sinar system

I currently have a 4x5 Sinar F. I want to move into 8x10 format shooting. Is it better to buy a separate 8x10 camera or buy parts, a new 8x10 rear standard and bellows to use what I already have?

Keep an eye out for whatever makes itself available, make a good deal where you can, and if you get parts you don't need, sell them off. Be aware that 8x10 Sinar backs come in two sizes, metering and non-metering, and you will want the back and bellows to match up.