Hi, I was at a loss when I could not find another side-by-side double stroller after "old-blu" died. Old Blu was a faithful companion to us in about a dozen different states and lots of trips out and about. (3 kids in 4 years) I had an old beat-up umbrella stroller and was given another one by my sister.

Bruce's DIY double-stroller (Recycle your old stroller when the next baby comes along).
1) Get 2 similar sized umbrella strollers. Use matching colors for brownie points with the Mrs.
2) Cut the wheels on the right or left side off of the oldest stroller with a hack saw so the center wheels will spin freely. Hey it was only $12 new! Save wheels for spares.
3) Attach them together using 3 hose clamps, avoid fold-up areas. Test fold, then trim clamps for safety. Nuts and bolts with spacers could work better. Enjoy!
4) Can be repeated for any number of strollers. You can restore one stroller back to single.