First, don't nick the seeds next time. I understand it never helps and can only hurt.

Are you sure you can't find any way to overwinter anything? I don't live in a climate with severe winters, but I understand there are creative ways to keep them that minimizes space and light requirements. Perhaps someone else can elaborate. Or perhaps you have zero possible space for any plant inside...

If you can't keep anything at all inside, there are a couple possibilities that come to mind:

1) Passiflora foetida will grow, bloom and fruit in one year, I'm told. I don't know if this works given the length of your growing season. You may be able to find seeds for postage or trade. Otherwise, you should be able to find viable seeds on Ebay. Looking at what's for sale right now, I would go with either the seller "where*the*wild*things*grow" or the seller "passiflorista" although others may also have viable seeds.

2) Get seeds or plants/rooted cuttings of a variety of P. incarnata that will grow in zone 5b, assuming that you can plant things in the ground. I'm not sure what a good source of those would be; perhaps others know. Not all varieties of P. incarnata are that hardy, and not all sellers will be honest (or knowledgeable) about hardiness. It's best to get them from a plant already growing in zone 5 for that reason.

3) Get cuttings or rooted cuttings of something that will bloom the first year and treat it as an annual. I'm not sure what would work, or what a good source would be. There are some like this where one can simply take cuttings in the Fall and bring them inside and repeat the next year. Cuttings would take less room inside than a mature plant. There are probably a number of species/hybrids that would work with this approach.