Where can we purchase type O morter mix so my husband and I can repair the brick foundation (ourselves) in our 1880 victorian house?

Thank you.

You can make your own mortar if you wish. Google Type O mortar and get multiple sites with recipe. But why would want to use this weaker mortar?

Ok so you are trying to match your old mortar and think it is type O, right. Problem is type O is an old low compression mortar so you might be right but can you match the sand color? Type O is a ration 1 portland to 2 lime and 9 sand. The sand will cause the color and texture you will see so its important to try to get the sand color to match. I'd make very small batches with different sands and test patch on the house. See what looks good and not.