The headword, presumably extracted from the first quotation given, is the aorist indicative middle, third person plural, of the verb periba/llw, I throw about, around, over; I put on); cf. pi 1077, pi 1078, pi 1079, and see generally LSJ s.v.
[1] The gloss is the aorist indicative, third person plural, of the verb e)pikta/omai, I additionally gain, acquire; see generally LSJ s.v.
[2] The quotation is not otherwise attested in this precise form, but, according to Adler, the German-Dutch scholar F.L. Abresch (1699-1782) drew attention to Xenophon, Cyropaedia 3.3.23 (web address 1). There Xenophon describes pillaging by the cavalry of Cyrus I The Great of Persia (Kurash, Kurush (Old Persian), Kyros (Greek); d. 530-29 BCE; kappa 2777, kappa 2778, and generally OCD(4) s.v. Cyrus(1)) prior to his invasion of Assyria: toi=s d' i(/ppois katadromh/n poihsa/menoi perieba/lonto pollh\n kai\ pantoi/an lei/an. This does seem close enough in wording to confirm it as the Suda's source.
[3] Philostratus, Life of Apollonius of Tyana 4.23; cf. pi 1077. Leonidas was the king of Sparta (c. 490-480); cf. lambda 272 and generally OCD(4) s.v. Leonidas(1).