Sorry for your issues man.
Doesn't sound like a starter issue. My best guess would be that the gear selector could need a good rebuild (easy to do it yourself if you have time or not too costly if you don't) or a safety switch which is fairly easy as well.
As for your transmission service, if you have never flushed your transmission before DO NOT START NOW. Lot's of members did a flush for the first time at higher mileage only to need a complete rebuild in a short time. Just drain the fluid, replace the filter, and fill the fluid properly as stated in the shop manual.
If you end up needing a transmission rebuild I don't think you'll be able to get that done for your budget of $1,500 depending on what's needed. If you have them start with just replacing the electric solenoids you'll have a chance. Many members have had shifting issues and just replacing the electrics fixed their problems. This does not require the removal of the transmission since they are located in the smaller pan and are fairly easy to access. If you do a search using the key word solenoid you'll find plenty of good reading and excellent help.
I'm sure others will chime in, but that's my .02 cents.
Hope you can get her fixed and back on the road soon!
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