Heart is a great red meat as is tongue. You can also do beef cheekmeat which is cheap also, but both cheekmeat and tongue are fatty, so you'd have to feed in moderation.
You could also try the ethnic markets, either asian or hispanic. Alot of times they have some really nice beef or other meats for very reasonable prices.
You could also try the ethnic markets, either asian or hispanic. Alot of times they have some really nice beef or other meats for very reasonable prices.