Yes. Triptherapie can guide you with a tripsitter if you bring your own magic mushrooms. They cannot supply mushrooms, as those are illegal.
Alternatively, you can choose legal magic truffles for your session. These are standardly available and you do not need to bring them yourself. Their effects are broadly comparable to mushrooms.
To discuss details and plan your session, contact the Triptherapie staff.
Hope this clarifies your options.