$1,000 a year in alimony is very little. One option might be to have him agree to pay higher alimony in place of the pension - but that could be risky as he might not pay or might quit his job and take off to travel the world. As I recall (correct me if I'm confusing your thread with another) you both are staying in the rental home because it is a good deal and you anticipate rent would be higher if you moved, correct? So maybe in place of alimony you could bargain for staying in your current rental, which would save you more than $1,000 a year?
The lump sum buyout is the other thing you can offer him.
One way to do a quick and dirty calculation - I love the Ultimate Retirement Calculator by Financial Mentor. It's free, easy, and you can run many different scenarios very quickly.
If I put in that you need $8,000 a year in retirement (in today's dollars, the pension value to you) and put in 3% annual inflation and estimate total growth in investments at 7.5% until age 65 and a more conservative 5% after that age, and estimate that you are 45 and will retire at 67, and live to age 90 - putting in as "present savings" the amount of a lump sum payment from H, looks like it would cost approximately $66,000 for him to buy you out with a lump sum that, if invested, would generate the equivalent of $8,000 a year in today's dollars, adjusted for inflation. IF he could come up with that money (or even, say, $50,000 and he takes on all the debt) you could either invest that money for retirement, or use that money as a down payment for a home if you think you know where you will want to live for the next decade or so. Being able to buy a home may or may not be a good investment for the future, many things are involved, but it you think it is likely that you would want to stay where you are, a home that you could pay off by retirement, that you could bring in income by having roommates, could be worth more to you in the long run than the pension.
You can also use this calculator to enter various values like your expected social security benefits, expected pension benefit from your job, retirement savings, inheritances etc. It has been invaluable to me in planning my own retirement finances. Also recommend you play around with assumptions about inflation and investment returns.
