One option (don't know if it's actually viable) would be to see a New York Yankees game at Yankee Stadium. It would depend on if they're playing at home when you go and if you can get tickets
There is also the New York Mets. Located at subway 7; subwaystop: Mets - Willets Point Station. Also the LIRR calls there (although 400 meters south from the subway)! You walk over the maintanceyard of line 7.
Home games New York Mets in May (prices start at 14 or 18):
California Angels: 19, 20, 21
San Diego: 23, 24, 25
Milwaukee: 29, 30, 31, June 1
Home games New York Yankees in May:
Houston: 11, 12, 13, 14
Kansas City: 22, 23, 24, 25
Oakland: 26, 27, 28
My view is that early season not all games are sold out. Yankees attendance May 2 and 3 against Toronto was 30.000 and 36.000 (roughly). Enough seating left!
More information can be found here: https://www.mlb.com/
A single ride on the subway is 3 $; 7 day pass 32. Choice quickly made i would say!