For $80 for both, I suspect your dealer is providing just the solid tire, not the tire/wheel assembly. The wheels on the F-Series are three piece bolted assembly so swapping to the solid tire is easy, no press required.
I purchased a set of solid tires only to find out that my wheels really need replaced as well - roller bearing inside was very worn. I bought the tires direct from Carefree Tire for $68 for the pair, including shipping and tax. I then found I could buy wheel and tire assembly for $100 for the pair so I decided to go that route. I now have an extra set of Carefree Tires that I would sell for what they cost me if anyone is interested.
I've found a source for the tire/wheel combination but they currently have the correct wheel on back-order. When I ordered what I thought was the correct wheel/tire assembly, the web site listed them as a replacement for my deck (RCK60-F30). However when they arrived I discovered they had a 5/8" x 4" hub/bearing, our decks need a 3/4" x 3-1/4" hub/bearing. I've since returned them and the seller has indicated he can get the right wheels, they are just back-ordered right now.
A couple of points about the recommendation from arto98607. The wheels he linked too are the right size, but they are white instead of orange (if that matters to you). Also the axle for the wheels would take a fair amount of work to make. I have a lathe and welder and I could make the axle from drill rod as arto98607 suggests, but new axles were $40 each on eBay and my time is worth more than that if I were to make them myself. They are not simple:
A further point, the wheels on our decks have a grease-able roller bearing that is not well sealed from the elements and is a location that is exposed to dirt, dust, grass, etc. I discovered I should be greasing these at a much higher frequency - every mowing or two - rather than the twice per season I had been doing. My axles were completely shot and the wheel bearings in rough shape as I mentioned.
It looks like I'll be a bit over $180 to replace wheels/tires/axles. I went ahead and bought all new ant-scalp rollers and a new axle for the large anti-scalp roller in front. Couple this with the replacement belt and tension and idler pulleys I put on this spring and it's cost me about $500 to refurbish my 16 year old, 700 hr deck too a like new configuration.
