um... Nope... Except state regulations... Emissions Testing... And expensive tickets for being caught without it...
My suggestion. Take it out, punch it out, and put it back in again.
What I would do. Take it out, sell it for scrap metal(convertors are worth good $$), and use that money to help pay for the straight pipe. Then just hope you don't get caught.
1988 Wrangler 89000 miles, no rust, no rot, all nice and pretty.. Runs down the highway really nice too.. This is great fun.