Look online at your state PERS system - they may have an online calculator that could give you a rough idea.
Yes, a QDRO may cost about a $1,000 - but it will be worth every penny if it protects your interest in his pension.
I would not give up your share of the pension unless the house equity is easily worth more.
How much does he have in his PERS account right now? The other thing that might happen is you get your share split off now via QDRO and transferred into an IRA.