The DotaLoot database has 380 items for Tidehunter, prices from $0.03. Rarities: Common, Uncommon, Rare, Mythical, Immortal. Any of them can be won from DotaLoot cases or claimed for free in the daily giveaways — noticeably cheaper than buying on the market.
You can get Tidehunter items for free in the daily DotaLoot giveaways. The fastest way is opening cases — noticeably cheaper than buying on the market.
The cheapest Tidehunter item costs $0.03. Prices update based on the Steam market.