Your best bet for regionals is to go to a sporting goods store or a clothing store and get the light weight breathable golf polo shirts.  Reebok makes some really nice ones.  then get your name embroidered on the back at least 2 thick letters and readable.  You can get fined and such for bowling shirts only that are not allowed to be worn.  Like there are some storm shirts that have VIP proshop on them and that is not allowed.  There can be no logos on the mock neck collar.  So the safest bet to avoid fines is to get plain golf shirts and get your patches there.  you need a name shirt durring practice too.  Atleast in the East region you do. 

Billy Trudell
Storm PBA regional staff
Drilling Tech Next Level Proshop

for my first regional,  I just had two plain polo shirts done up with my first and last name in bold letters on the back...  nothing fancy or wild just plain n simple...