I only know something about grafting, not much, but am willing to share what I know.
I would do like Brady suggested, plant a bare root Satsuma and let it establish a bit. When it start leafing out, you could graft Toka on it. I personally won't do it that way. I want a new tree to grow for a year and then graft the year after.
When a tree is newly planted in ground and starts to grow, sometimes, it does not don't have enough energy to push for growth of a new graft (say Toka). That's when a graft fails.
Don't worry about acquiring scionwood, people here are generous. Usually, someone would be kind to give you the scionwood you want.
I saw you have a beautiful pear tree. If I were you, I would ask for scionwood of pear varieties you want over the winter and then graft those scionwood to your existing pear tree in the spring. The chance of successful grafting will be high.
There are a few threads about how to store dormant scionwood in the fridge so it would stay dormant (and not get modly) for a couple of months before you are ready to use it to graft.