How should I phrase "please contribute to swingset instead of buying other toys"?

My son is turning one. I want to use an idea my sister-in-law used…she asked people on my nephew’s invitation to consider contributing to one large gift, in the form of a gift card, instead of purchasing a bunch of misc. toys. I can’t remember how she phrased it. When I try to write something, it doesn’t seem polite. I have a small house and really can’t have several more noisy toys. I also love the idea of a swingset, which I can’t really afford, b/c he loves being outside. How can I phrase this politely? Thank you!