DA carries them. For the DL50 you need the MTW wraparound header. For most planes with a 25mm drop. I recommend going for the solid header, not the flex. And you need the Teflon coupler of course, 2 clamps and a 55mm canister holder.

This was my last order:

MTW wraparound header for DA 50 with 25mm drop
MTW RE2 Pipe
Teflon coupler kit, for 25mm dia headers
MTW Plywood canister holder, 55mm diameter

You need to run a 23x10 prop with this combination like the Vess 23B.

Edit [8D] If you break your engine in well, you can squeeze between 7200-7300rom out of this combo with a Vess 23B. That's over 35lbs of thrust.