I think you cannot miss with several pair of black slacks, maybe white and tan for Spring. Pair them with some jackets and neat shirts and you are business casual.;)
Business casual differs from company to company. A place i worked, refular dress was a suit with a skirt and business casual was the same suit put with pants, but that was the very beginning years of business casual becoming popular. Yeah, it was a big deal to wear pants for us, we were kinda boring weren't we? I am assuming you are meaning a bit more relaxed than that. You can still do a lot with the suits you own for the time being. Wear a skirt from a suit you have with a blouse or even a much more casual top...like the kind that are just pullover knit short sleeve tops and wear a scarf with it. something you already own. skip the sky high heels but accessorize. get working there for a few weeks and sort of check out what other people are wearing and then look just a bit more polished or pulled together then they are which will probably be easy to do if you find out everyone is rolling into work looking like they just rolled out of bed.
