>I can't afford to bulk on chicken breasts and eggs
just don't,
first of all, don't fall for the bulk/cut meme, just eat your proper macro, enough protein and healthy overall diet
>alternatives
beans and pork are a great staple, pork meat is great and largely underrated
lentils, are not your only option either, corn and peas come cheap as fuck in those tin cans, and provide a great supplement for clean carbs+prots
don't underestimate eggs, milk, bread, cheese and similar, the literal bread and butter, these are staples in every western society and provide nutrition if used smartly
nuts and cereals in bulk as your pic related can't hurt either
if you really lacking protons after all that, consider the whey like post above,
but literally that is a sup for nutritionally dumb people