I can't find regular version of Ornithomimus Hat and I'm pretty sure it's available in GF as regular item. Donation NPC sells only 7day and 30day version(and 7day is twice on list).
13092 Ornithomimus Hat 30-Day Pack
13116 Ornithomimus Hat 30-Day Pack
13288 Ornithomimus Hat 7-Day Pack
13353 Ornithomimus Hat 30-Day Pack (Event)
13377 Ornithomimus Hat 7-Day Pack (Event)
12790 Ornithomimus Hat 30 day limited period
13245 Ornithomimus Hat 7-day Limited Period
13316 Ornithomimus Hat (Event) 30-day limited period
13331 Ornithomimus Hat (Event) 7-day Limited Period
that's all there is in the database/itemname.dat.
for example: http://l2.dropspoil.com/?s=ornithomimus+hat
In that case, please close/remove the topic. Sorry for misleading bug report.