There was a company here in the UK that used to sell phosphur/bronze swing arm bushes that were an exact replica of the plastic items on my 750F2. I bought a pile of these & used them on a friends CBX1000Z as well as my wifes 550F2.They were simple to install & made a big differance to the CBX. Luckily this modification was done on the bikes when they were low mileage, so there was little if any corrosion or wear on parts that had been regularly greased.
As has been said, the use of just a hacksaw blade to cut out the old plastic items was the best way to remove them. While the arm is off it's a good time to clean out the old grease from the cavity & the zerk fitting. The seal on the end caps & the spacing shims should also be checked.