Any idea how old these weaned calves are? That would probably play a role in profitability. They
should be profitable at any rate (excepting, of
course, massive death losses, which is unlikely but happens), the question is just how profitable.
But if you've got $1500 or more to spend, you might consider buying a bred heifer of one sort or another, which ought to be doable for around $1000. When she calves, buy another newborn (week-old-ish) calf (maybe $200) and graft him onto the new mama. In about three months have her bred back. You've only got at most two calves for butcher (one, if the heifer's own calf was a heifer and you decide to keep her), but you've also got a leg up with the start of a breeding herd.