HI Chris,
I bought my Lunt Ha filter second hand via IIS. It originally came form Sirius optics
http://www.sirius-optics.com.au/telescopes.htm . They look like they go for $1275 for etalon and B600 blocking filter/diagonal. If your focal length is longer than 600 mm you need the B1200 instead of B600, which is also necessary if you want to image the whole disc. there is no problem viewing the hole disc visually with B600. You buy an aluminium ring to attach it to the front of the scope and I don't think they cost much.
I will have mine at Snake Valley next weekend so with clear skies you should get a good preview.
A fantastic investment in my addicted opinion.