Trailer Tires 195/65 R15

Hello USA.

In late June, I'll be driving my restored Schleicher ASK-13 from
Marfa, Texas, to the International Vintage Sailplane Meet (IVSM) on
Harris Hill, near Elmira, NY.

Ready to replace the tires on my enclosed Swan trailer (a Cobra copy),
my local tire suppliers cannot find the "T" or "ST" for Trailer in
size 195/65R15.
They say that 195 size is only available in P (for passenger) which
has a slightly lower load rating. Closest size in T for Trailer is
205/65/R15 which are a bit too large for the existing fenders.
Trailer loaded with glider total weight is about 2600 pounds.
Any sources for the original 195/65 R15 T or ST trailer tires out
there?
Otherwise I'll modify the fenders.

I only drive 55 mph (5 mph over the German 80 kph speed limit for many
glider trailers.) The big Swan trailer is quite tall to accommodate
the wide chord of the ASK-13 wing root. I stay off Interstate
highways to avoid the trucks (and not be a slow-moving hazard) and
take the scenic backroads across the USA, which are often smoother and
a more relaxed, interesting route than the Interstates.