....snip...

It's unlikely I'll need to drill more than a couple of holes so was
trying to keep the cost to a minimum.

I appreciate SDS would be better/faster but the time it takes me to
drill them isn't a big issue.

I hired an SDS and purchased an SDS bit from a local firm a few years ago.
Wasn't too expensive and the difference in time and effort was well worth
it. If you're drilling a core I believe you can hire those bits.

Paul DS