Actually, I would say the disposable 8233 has definite benefits over a cannister type respirator. For one, every time you open a new one you are starting out fresh. With a permanent type, you always have the risk of contamination from airborne particles due to not quite right storage conditions or handling.
In any case, I buy mine from Cyberweld. Price is lower and free shipping with a minimum order of $25, I believe.
http://store.cyberweld.com/3mpare82n1.html
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