I prefer to use full AA size lithiums to replace mine.
Digi-Key - 439-1010-ND (Manufacturer - TL-2100/S)
You can then wire
two AA battery holders ( in parallel) into the circuit ( just hot melt glue them somewhere conventient to access) and away from the
board before you start to remove the original battery. When ready, pop in a AA in one holder ( mind polarity), and cut the original battery out of the circuit quickly.
If you then ever need to replace the AA you just pop another AA in the second holder and remove the first.
Of course this is probably overkill, as the battery will probably outlive the receiver now.
If you are in dire need of a battery
quickly Radio Shack usually has the AA tadirans in stock for about $20.