I think Warwick tuners are in fact made by Schaller anyway. I have recently replaced the chrome hardware on my Corvette with black hardware, and found that buying new Warwick tuners from Thomann was way cheaper than buying from Schaller, and the Warwick ones are good and hold the tuning perfectly. What's wrong with the ones you'd like to replace?
I am talking about normal weight tuners here. I looked up the Schaller ultralightweight solution, and they are horrendously expensive. Before I decided to go for the normal weight Warwick ones, I had a word with the guys at Tonetech, who suggested that a cheaper solution, if I wanted lightweight tuners, might be to use Gotohs. Quite apart from the fact that I didn't like the look, I also noticed that they were almost as expensive as the Schallers, and the actual weight saving isn't as huge as one would hope for the price.
These were suggested by Bill Quinn of Tonetech: https://g-gotoh.com/international/product/gb350.html
Their weight, including bushing, is 40g each.
If you are interested, do get in touch with Tonetech, who should be able to offer a better deal than buying direct. (I am not connected to the company, I simply met Bill at the London Bass Guitar Show, had a few long chats, and he definitely seems to know what he's talking about!)