NB while the SRS is UK-based, your submission does not need to be Anglocentric, nor do you need to be an established scholar to make a chance - and “early modern / renaissance” is interpreted generously. I submitted my PhD-turned-into-a-book on late medieval and EM Dutch chronicles from a Dutch publisher, and the jury took it seriously, between submissions from much more esteemed colleagues in much more established subdisciplines https://www.rensoc.org.uk/funding-prizes/society-biennial-book-prize/