Aliyah to the Torah on a Holiday When a Close Relative Passed Away During Chol Hamoed

If someone's father passed away during Chol Hamoed Sukkot, is he allowed to have an aliyah to the Torah during Chol Hamoed?

It is not advisable to appoint him among those called up, but if there is no other Kohen there except him, it seems he can be called up.

Mishna Berura, Siman 548, S"K 16: "One who died during the festival is prohibited in private matters such as bathing in hot water, marital relations, and Torah study, and mourning is observed, and it is forbidden. However, some permit Torah study. Nevertheless, regarding being called up to the Torah during the festival to include him among those called up, it seems that initially it is not advisable." Regarding Shabbat, the Rema writes in Siman 548, Sif 1: "If the Kohen is in mourning and there is no other Kohen in the synagogue, it is permitted to call him; but in other matters, it is forbidden." In the Pischei Teshuva, it brings the Shu"T Chatam Sofer, who wonders why the Rema did not write that it is preferable to leave, since the Maharam of Rothenburg, who is the source of this law, wrote that it is preferable to leave. And he concludes: "Nevertheless, it is clear that if the Kohen usually leaves the synagogue to call an Israelite in his place, then even when he is in mourning, there is no such public mourning if he leaves the synagogue. Nevertheless, if he does not leave and he is called, there is nothing wrong with that." But regarding the festival, which is lighter than Shabbat concerning mourning, there are several reasons to permit calling him: 1. Perhaps there is no mourning in private matters during the festival at all, according to the Rambam. 2. Even if there is mourning in private matters, perhaps it is only during the seven days of mourning, but Torah study is permitted, as written in the Shu"T Chacham Tzvi, Siman 100. 3. Even if it is forbidden to study Torah, perhaps the Rema holds that even on Shabbat, if there is no other Kohen, he is called up and does not need to leave. And even the Mishna Berura writes that it is not advisable to call him, therefore it seems that it is possible to be lenient if there is no other Kohen there except him to call him to the Torah.