That"s my budget every year. So here’s what I found:
Easy Peasy Homeschool (allinonehomeschool.com) It’s a full curriculum but I only use it for Bible, History, Science and electives
For reading I use the Ambleside Book list. For Phonics, I would suggest Teach Your Child to Read in 100 Easy Lessons and Explode the Code. Spelling Zaner Bloser Spelling Connections has word list and worksheets.
Math - I got my math nearly free Math Mammoth grades 1-6 for $75. You just have to see when they have a sale.
I’m also looking into Expedition Earth, Road Trip USA, and Confessions of a Homeschoolers art and musuc (can’t remember the names).