Ornament can't find would like to figure out a good substitute

It's called (at least, in MuseScore) a "slide".

1. Enter the note that it is to affect.
2. Select that note.
3. On the Palettes tab, open the Ornaments palette. If it's not displayed there (and it probably won't be!), click the More button at the bottom of the palette.
4. You should see it in the More list. If you don't, try mousing over each item in the More list until you find the one named "Slide".
5. Click it to add it to the note.

MuseScore places ornaments above the note. I believe this is correct modern usage, but I know that they were placed in different places in the past (according to the handful of ur texts I've seen). Personally, I would leave it above, but if you want it next to the note as your screenshot shows, move it as follows:

a. Click the ornament to select it.
b. Click the Properties tab.
c. Click the Appearance button.
d. Now, adjust its position with the two Offset fields. FYI: the horizontal Offset works as I expect, but the vertical Offset works exactly opposite what I expect. Be aware of this and experiment to move it where you want it.

Good luck! :-)