We have a low income as well (one teacher and one full time student) and we have found that being vegan (no meat or dairy products) is much more economical for us. Meat was so expensive as are dairy products.
So we will have any two veggies (frozen or fresh) maybe beans, or rice, potato, etc (these are just some examples of what we eat.
And we are able to get a full nutritional diet without meat or dairy.
I think giving an extra offering is a fabulous idea.