Making a seat is your own DIY solution. As I wrote, I made that from vaping 510 driptip sealing rubbers - I'm vaper, many in stock.
But you can enjoy the benefit of the seating with the P1 own foam tips as well. The Acoustune tip gives a little enhancement to base section, a little more tightness and layering, but its foam tip still good.
My AET07 tip I got from Acoustune on an audio event in London two years ago, I didn't order that
Btw good tip. I used with several different iems those compatible with, and I got the best result with this tip always.
Btw, did you receive the AET07A tips yet? I haven't ordered the Acoustune tips since they are a bit pricey. My Auvio tips have a thicker core versus all the other random tips I own. I think that's why I'm getting a better bass response with them.
This has been my P1 bass response test track while checking out tips....