The Deschutes chips overclocked really well- the core is made for 450MHz, and the manufacturing process was so good, practically every chip could get there without even a voltage bump I got my 333MHz (5x66) up to 400 (4x100). Unfortunately, the LX only supports a 66MHz FSB, but you can probably get it up to 75MHz.
Whatever you do, crank that chip HARD- If you can get the FSB up to 75MHz, that's a great start. Otherwise, I think the 300 was still multiplier unlocked; not that it does you much good, because you can only raise it to 5 or 5.5, but you should be able to at least get it to 333 (I know the 333 was the last chip Intel made without the multiplier lock on) Let us know how it goes!
Pentium IV 2.4C Northwood- M0 stepping @ 3.2GHz HT
Air Cooled w/ SP-94 heatpipe & 92mm Vantex Tornado at 45C
4x256=1gb dual-channel 2-3-3-6 OCZ PC800DRAM @ 890MHz 3-4-4-8
MSI Neo2-PLS w/I865PE & SATA @ 4x267=1068MHz
BFG GeForceFX 5900@485/967MHz = 6284 3DMark2003s; dual-head 21" CRT & 19" LCD