Both Perez and Leyba/Leyva may be traced to Spanish Jews some of whom initally came to Mexico during the various inquisition years (1492-1700's)The Roman Catholic Church sought purity of Spain initally via King Ferdinand and Queen Isabella who unified Spain in 1492 (also sent Christoval Colum [Christopher Columbus] on his way).Jews had traveled to Iberria (Spain also may have been known as Sephardis [also mentioned in the Old Testament] thus Spahish Jews are also known as Sephardic Jews) during several dispursions from Israel as early as 300 BC.When the Muslims or Moors conquired Spain and ruled most of it between 800-1100 AD many more Jews came as they became experts in trade and business.The Moors trusted the Jews who became their business partners and businessmen in trade.As the Moors were eventually conquered, Jews were also targeted as they were also not Christian.In 1492 an edict was made giving the Jews about six mos. to convert, leave, or die.This, of course is the very short history as Jews had suffered immensley at the hand of the Church and local civil governments of Spain as early as 1000 AD.
Many Leybas/Leyvas and other Sephardic Jews, besides going to the new world, etc. also ended up in Eastern Europe as well.In the new world, however, the R.C. Church began their inquisitions with sites in Mexico City, Lima (Peru), and I believe Columbia somewhere. In the new world the target wasn't the Moors but rather the Natives (indians)of South and Central Americas.Their baptism or death was required by the new civil religion of the new world.
Most likely my relatives whom I can trace back to Santa Fe in the early 1600's (Leyba) were likely Sephardic Jews moving to Santa Fe, the most northern place one could go to to excape inquisitions in Mexico City during the 1500's.Of course over the next hundred years nearly all Sephardic Jews in northern New Mexico all converted (unforced)leaving nearly all traces of Judaism behind and being fully assimilated into the Catholic faith.However, New Mexico geneologists have found or known of some New Mexicans who, while being Catholic, practiced sabbeth keeping by lighting their candles at sundown on Friday evenings.Of course they didn't know just why they practiced such things believing it was just a family tradition.
Leyba/Leyva are likely transliterations of Levi or Levy.It was common for families to chose famous Old Testament names for both first and last names.Perez is a direct translation of a Jewish King in the Old Testament.The fact that both are in your family may mean there was once a connection that both had, possibly a sephardic jewish heritage.
You may want to inquire about the Sephardic Jews as much research has gone into their study in the past 10 years.
My wife's cousin's husband whose name is Cordis not long ago inquired about his "German" roots.He discovered that Cordis is not a german name and that the name was likely Cortez, a comon Sephardic Jewish name.King Ferdinand's mother was Jewish....don't know what happened to her in 1492.Enjoy you research as we may have some common roots.
The person who has done some research assisting me to find the Leyba/Leyva connection is a Betty Pacheco of Pueblo, CO.Her data in in "FamilySearch" of the LDS.I plan on meeting with her in a few mos. to go over some of her stuff.
Given the dates you indicated, your Labor or Leyba may have been one of the "converso" families retaining their name but becoming Catholic very early on.Good Luck!