My guest list swelled

Get a ham. No one in my family likes turkey...some of your guests might not be turkey fans.

How about getting just a turkey breast? Those thaw out overnight as a rule, and are easy to roast. Most people go for the white meat anyway. It could probably bake alongside the full size bird you have now, though it won't take as long to finish.

Hi NR, Happy Thanksgiving!

Some ideas here: You'll want to figure about 1 1/2 lbs of turkey per person at the generous end, making your 11-pounder work great for 8 folks. If you can find another small-ish turkey, that will help supplement the extra 6. You could also try the turkey roulade from Trader Joe's (sounds yum!) and fill out the table with additional sides. Here are some of our tried-and-true favorites, plus a few new classics: https://food52.com/blog/23373-best-thanksgiving-side-dish-recipes

Hope this helps!

At this late date, get what you can find, know how to cook, will be comfortable serving.
Maybe even another kind of meat, or poultry.
Offer everyone at least some piece turkey and/or the second roast beast.