А про Родольфуса известно, что он учился вместе с Беллой - следовательно, более или менее ее ровесник. А Белле было 30 в 81 году.

Сириус, 4 кн
“Snape knew more curses when he arrived at school than half the kids in seventh year, and he was part of a gang of Slytherins who nearly all turned out to be Death Eaters.” Sirius held up his fingers and began ticking off names.
“Rosier and Wilkes—they were both killed by Aurors the year before Voldemort fell. The Lestranges—they’re a married couple—they’re in Azkaban. Avery—from what I’ve heard he wormed his way out of trouble by saying he’d been acting under the Imperius Curse—he’s still at large.