Just get a coupling like you would use to join two long pieces of pipe. Cut your pipe in the middle and insert into the coupling so that you sweat 1/2" on each end into the coupling. $5 instead of $70. With a 2" coupling, that should give you the extra 1" on the end that you need.
In the old days you might have found in Big Orange a scrap bin with cutoffs from people who had pipe cut to size, much the same as lumber scraps, but with the price of copper today, not so likely.
Insert to the full depth.
Clean the pipe and fitting - I use scotchbrite, that fibre green pan scourer, for even “new” pipe and also I do the inside of the fittings. Then flux on both the pipe and fitting, I then find the solder runs around from a single point of contact.
The professionals who use a bag of fittings a day don’t bother, but I have fittings from 5 years ago…
Not inserting to the full depth could mean that the pressure fluctuations over time could break the weaker solder joint.