No, your multipliers were correct and I was just using 1500 as an example of a maximum (though modest) attainable speed.
The letter suffix designates a core change from a previous model with the same clocks. 1.0 and 1.1 are Coppermine (1.1 being the last). 1.1A is the first Tualatin which as you know is preferred.
Compare your rig to those in the overclockers database for the 1.1A, 1.2, 1.3, 1.4 to help decide which is best. If you do not want to overlock the chipset or cannot retain sync beyond 133, then perhaps the 1.2 would be best, being a l'il faster but without too much of a gamble and the cheapest price to boot (from those you listed).