Covid Plan b - Outdoor Ceremony Location in Chicago Area

I've started the search for an outdoor wedding ceremony spot in the Chicago area (ideally west suburbs) if we need to reschedule our June wedding, just in case. We still want to actually get married on our wedding date with a very small group (probably just wedding party + parents), but I'm having trouble finding an inexpensive spot to just have the ceremony - does not need to be a full out wedding venue...looking at gardens, wooded areas, etc - something unconventional and cheap! since we'll still be having our actual reception at a later date. Thanks for any input!