Starting a private pension

[Kaffiene]

I am trying to work out how to best plan for my future. I am 50, single parent to 2 children who get disability benefits. I work part time and have a very small work pension I just started a few years ago. I rent a council house.
Currently I get a top up from UC due to the my kids getting DLA but after years of wrangling I am finally getting Child Maintenance including back pay and it’s a fairly healthy amount each month.
My kids will be adults in 7 years and I won’t be entitled to UC anymore and the CM will stop, leaving me in a very different financial situation. I can’t pay anymore into my work pension than I already do as it would take me under NMW for my hours.

Should I open a SIPP and pay as much as possible over the next 7-10 years and use this to top up my income once I am not longer entitled to UC. It is unlikely I will be able to increase my hours due to my kids needs. Even when they are adults they will not be independent.
Of are there better options for me?

You should still be able tonoay into your work pension can’t you? You’re still getting the wage - just choosing to put it into pension instrwad?

No because it would bring OPs earnings under NMW, which isn't allowed. Op I would open a SIPP but be aware that whilst the current age you can start to withdraw from a SIPP is 57 this is likely to rise inline with state pension age rises ( currently set at 10 years before state pension age). So may be worth saving some in a long terms saving vehicle (ISA) if you will need to access from age 57.