The place I bought my bike from in Kaukauna, WI will match online prices so I normally pay whatever motorcycle-superstore.com has the tires listed for (currently $188 for the 50, $196 for the 55). They charge $35 per tire if its on the bike, $25 off the bike. I know to some people $10 doesn't sound like much for the added time of removing tires yourself, but if I remove the tires I can stop in whenever and they will mount the new ones in 15 minutes. If I want to bring my bike in, I have to pre-schedule and leave the bike there for an hour or two which isn't always an option for me.
I should also add when I bought my PR3 front last month it was also listed as "backordered" and even my dealer originally said it would be as well but it still arrived in 5 days. I would say order it now either way - I don't believe in patching motorcycle tires. Sure they are expensive but unlike a car tire, motorcycle tire failure will almost always hurt.