Gavor played rugby for Rondebosch Boys' High School in Cape Town, but was never included in any high schoolrepresentative sides. He first represented Western Province during the 2012 Under-19 Provincial Championship; he made five starts and four appearances off the bench during 's matches in this competition, scoring two tries in their 55–11 victory over as Western Province finished top of the log. One of his replacement appearances came against in the semi-finals in a 24–14 victory and he was also named on the bench in the final, but failed to make an appearance as his side beat 22–18 to clinch the title. Despite being included in the squad for the 2013 Varsity Cup and the squad for the 2013 Under-21 Provincial Championship, he failed to get any game time in either competition.
He moved to Johannesburg in 2014 to join the. He was included in university side 's squad for the 2014 Varsity Cup. He didn't make any appearances in the competition proper, but was included on the bench for their relegation play-off match against. However, he was unused in their 42–8 victory to retain their Varsity Cup status. Shortly afterwards, he made his first class debut for the Golden Lions in the 2014 Vodacom Cup by starting in their 110–0 victory over the in Polokwane; it took him just nine minutes to score his first try in senior rugby as he got the second of 16 tries in the match. He got another try in their next match, a 27–48 defeat to the, in their final match of the regular season to help them qualify for the quarter finals. The Golden Lions secured a 27–20 victory over a in the quarter finals and a 16–15 win over the in the semi-final, as Gavor scored the Golden Lions' only and decisive try just before the half-hour mark. He also started the final, but ended on the losing side as won the match 30–6 to win the competition for the fifth time. He made eleven starts for the side in the 2014 Under-21 Provincial Championship, scoring eight tries, helping them qualify for the semi-finals. However, despite beating the Blue Bulls twice during the regular season, they could not repeat the feat in the semi-final, losing 19–23 to their Gauteng rivals and eventual champions. Gavor made two more appearances off the bench for the Golden Lions during the 2015 Vodacom Cup competition in their two matches against the Pumas; a 24–16 victory in Nelspruit in Round Five of the competition and a 20–43 defeat in Johannesburg in the semi-finals. He was included in their Currie Cup squad for the first time in 2015 and made his debut in this competition by appearing as a late replacement in their final match of the regular season, a 29–19 victory over.
