I would be tempeted to take a level of cleric in place of Egoist for turn undead to allow alternative sourced spell and divine metamagic persistent spell madness. If you were neutral, you could even through a level of Dread necromancer in to get both postive/negative energy (or dragon and negative energy) channeling. If you did this, you next item purchase would be easy, Nightstick for 7,500gp and a Holy Requilary system (ick spelling) for 1,000 gp to net you 6 extra turnings.
For your alter self wand, I might be tempted to get an eternal wand. Ony two charges a day, but it will never run out.
Also I might drop that +3 mithral buckler. With your chameleon you should be easily be able to cast Magic vestment. Spend a little more money and pick up an +1 animated large mithril sheild with the feycrafted template (+1,500gp) from DMGII. This will eliminated the last 5% spell failure on the shield and make it 10% lighter in weight. Base it will have one less point of AC (2+1 enchanement), but magic vestment it up to a +5 for a total of 7 points of AC. Don't forget the sheild spikes and enchant it with Spellblade. Spell blade costs 6,000gp (8,310 gp total with the masterworked spikes, +1 weapon, and base spikes cost) and lets you pick one targeted spell you are immune to, select greater dispel magic. If you have lots of buffs, this will force the enemy to use the area version of the spell which can only take out one spell (and only after he figures out you are immune to the targeted version). If you are really worried about it, there is also the ring of Enduring Arcania in Complete Mage that adds +4 to your caster level for purposes of the enemy trying to dispel your effects for 6,000gp.
Same goes for your armor if there is any armor properties you would like to add to it later. Magic vestment is the way to go. One I like if you can swing it is the +4 soulfire enchantment from the Book of exalted deeds. It makes you immune to death effects, energy drain, and negative energy effects. Changing your armor from a +3 to +1 with soulfire will up the price from 9,000gp to 25,000gp, which should be well in your range of remaining 50k loot.
I think that puts us at 40k gp if you do all of the above plus whatever it takes to make the wand eternal.