Try Hobby Lobby, Michael's or other places that have dried flower/plant arrangements. I've bought lotus pods from Hobby Lobby in the past and the seeds sprouted.

I found an old one, have been soaking it for over a week and nothing.

You have to scarify the seeds or they'll never sprout. They found a lotus seed in china that sat for 1200 years without sprouting. Just use anything rough and scrape into the side of the seed a little bit and put it back in the water. You should see the seed start to swell in a day or two.

Easy to buy on ebay. I've had a lot of success with germinating the seeds. Some sellers scar them and send them so that you dont have to.

https://www.aliexpress.com/item/10-Seeds-Pack-Hydroponic-Seeds-Water-Lily-Mini-Bonsai-Seeds-Plant-Water-Bowl-Lotus-Seed-Easy/32791849264.html?src=bing&albch=shopping&acnt=42005546&isdl=y&aff_short_key=UneMJZVf&albcp=133368713&albag=5555450757&slnk=&trgt=pla-4584894769298546&plac=&crea=13195869849&netw=o&device=c&mtctp=e&utm_source=Bing&utm_medium=shopping&utm_campaign=PA-Bing-Home%20%26%20Garden-US&utm_content=All&utm_term=mini%20water%20plants%20for%20sale&msclkid=7d5f09b765da16d6d9b353d778955768