To those that have 'em broken and/or have difficulties obtaining right width/teeth/composition in required length:
you can easily braze (silver soldere) blades yourself, for real cheap (a little HomeDepot butane torch, some brazing silver and flux). Results are excellent - in terms of appearance and strength.
So if you have broken a blade, or looking a size that is not readily available, brazing is the way to go.
File the ends so that they taper a bit and overlap over 3/16-1/4 distance. Clamp down one end, apply some flux ($.001 worth), clamp down the other end on top, so that tapered ends overlap, snick in (between) a
1/4 strip of .005" brazing strip ( $0.01), heat up till silver flows, file off excess (after it cools down), anneal a bit ( warm up to before silver melts, back the flame away slowly, repeat 2 times) and you're done.You can use a piece of scrap aluminum/steel and couple of smaller C-clamps to clamp the blade on, or make yer own jig. Make sure to file off an identation under the overlapping portion of the blade, so that you can heat it up. keep the size of the jig down (it will conduct the heat away from the joint).
Now - to make your own size, buy an oversized blade from Sears/HomeDepot/Lowes, reduce it in size and braze. You might want to reduce it so that the old joint is cut out. To break/cut the blade: cut a groove with a few moves of a sharp file edge (tapered files are best for that) and then snap the blade at the groove. Be careful as steel is tempered and will try to spring up on you. Buy next closest large length blade: if you need 62", get 64 1/2" (not a 111"). Do explore making 2 blades out of oversized one, to save even more.
For advanced moderate-to-heavy setups, welder might be a better choice. Also, if you go through blades quickly (as in wear them off), buying blade in bulk might be the way to go.
All of the above applies to both metal and wood cutting blades. I didn't invent the process :) - just refreshing the subject .