I sourced the 2hp 3-phase motor ( TEC ) and matching Huang Yang vfd for my mill from separate suppliers on eBay. Under £210 for the two. Lower rated motor and vfd would be commensurately cheaper I presume. Plenty of choice on various auction sites if you search hard enough. Enjoy your lathe when you get it running.
Bosch Rexroth for me, great unit very compact, fits in cabinet with remote panel fitted on my ML7 headstock. No great big boxes to accommodate. Highly recommended.
To remotor my Unimat I bought a nice brand-new Parvalux 3 phase ~1/8 HP from "h4ab" on eBay for 39.99 squids. Not available now but bargains around. Huanyang VFDs are very cheap.