for tires themselves, there are name brands then there are off brands. price can be 2 to 3 times as much for name brand tires.
open up phone book to auto/tire change places, and just start calling. you may have to call 40 to 50 places, but as you call just make sure you have a good working pen and paper, to quickly jot down names and phone numbers. due to some times folks know who, and will just spit it out and will want to quickly hang up.
also get on the internet and do a search for R1 tires, for places a couple hours away. prices can change rapidly. and some times it is that place 2 hours away that has things in stock, and will deliver and install them for less than some place locally.
if you are going with filled rear tires, having someone come out to do it, can make things easier on you for any were from 50 to 200 bucks. they will have the heavy duty jacks, larger size toque wrenches, and if need be a small crane on the truck itself, to lift tires and move them on/off trailer. and onto tractor.
personally prefer a thicker harder rubber tire. (uth oh been to long to remember) i want to call say instead of an R6 or R8 go with R10 or R12. thickness for the rubber. the thicker/harder rubber will give a rougher ride on tractor, but for me running over a thorn bush, or peice of metal. the thicker / harder rubber tires will less likely get cut and get a hole in tire.
it is normally fairly cheap to get "tubes" installed at same time. for me running over thorn bush or like, just a little more rubber a thorn or nail or like has to go through, before i get a leak. if you go with filled rear tires, a tube gives you a few more options of what you fill the rear tires with.
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i would be very cautios of buying second hand tires. without seeing them first in person. most dealers may get a request from a customer to have different tires put on, before actually buying a tractor. the new tires that were on the tractor, normally need to be sold to some recycling place for tires. and dealers not allowed to re-sale those tires that were taken off. there are a few places that are allowed to re-sale these tires, and other old tires taken off of other machinery. and you may end up getting beat up ready to fall apart tires. or tires with cuts and cracks through side walls and everything else.
for R1 tires, thickness of tread can be very important. if tread is gone, you end up with R4 loader tires and loose your traction abilty in the mud.
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one last note do search here on TBN, to see about putting groves into R4 tires for better traction, along with putting on chains on the R4 tires.
errr one more last note, if your tractor is 4x4 or MFWD or like, you will need both new set of rear tires and front tires. so you keep the ratio correct. and do not tear up the front end of the tractor.
