The lower part of the bracket is available from the dealer, as are the bolts to attach it to the upper bracket and to the downpipe. About $20 total, I think. It is likely to be special order, so will take a couple of days.

When I replaced the downpipe on my 245, I was able to remove the bracket from the old one by cutting the old rusty bolt with a sawzall.

Use some sort of temp-resistant threadlocker on all 3 of those bolts (plus the two holding the upper bracket to the bellhousing if you're taking that off at any point) or they WILL vibrate out and vanish in short order. And if you opt for hardware store bolts instead of dealer bolts, splurge on stainless steel!

good luck!

John