Yes, BASTERS is a Scrabble word!

Letter values in Scrabble US: B 3, A 1, S 1, T 1, E 1, R 1, S 1.

Is it a valid word?

BASTERS is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a cook who bastes roasting meat with melted fat or gravy
a sewer who fastens a garment with long loose stitches
a tube with a rubber bulb used to take up and release melted fat or gravy in order to moisten roasting meat