Yup, I breastfed with a Lact-Aid (which is a thousand times better than the SNS, IMO) for over a year then stopped supplementing but kept nursing when DS1 was a toddler. I had five units, which was perfect because they could be washed and loaded once a day - a great job for a partner, BTW.
I just nursed "bare" at night but if you need to supplement at night I'd just keep a small cooler next to your bed. A small insulated bag with an icepack is handy for traveling with the filled Lact-Aid units.
I wish I'd had the book "Making More Milk" with my first son.
If you give me a few more details about your situation I may have more advice...
Megan, loving her sweet boys, born Aug. 2008 and Feb. 2011, and their sister, born still March 2007