Rich sources of calcium include: Leafy green veggies like kale, escarole, collard greens and bok choy. Nuts like almonds and pistachios are good sources. Dairy and some fish, whihc you say you do not eat, are of course good sources. Do you not eat dairy because you are intolerant or ????
According to Michael Holick, if you are between 19-50 years, he recommends 1000mg/day of calcium. If you age 51 or older, that goes up to 1,200mg/day.
Getting an adequate calcium intake may be difficult with your stated food exclusions. If you choose to take a calcium supplement, calcium carbonate or citrate are both well absorbed and may be taken with or without food. Absorption will be best if doses are equal to or less than 500mg each. Taking the supplement with meals can make possible side effects like gas, bloating, constipation or combos of all 3, less of a problem, if they are an issue. Taking smaller doses at each meal can also help.
Vitamin D is essential for the uptake of calcium.
If weightloss is an issue for you, Michael Holick has this to say about calcium and D:
"Weight normalization is associated with higher levels of vitamin D and adequate calcium.
When the diet lacks calcium, there is an increase in fatty acid synthase, an enzyme that converts calories into fat. Higher levels of calcium with adequate vitamin D inhibit this enzyme, while diets low in calcium increase this enzyme BY AS MUCH AS FIVEFOLD. More of this enzyme's activity means more fat getting stored from calories coming in. In one study, genetically obese rats lost 60 % of their body fat in six weeks on a diet that had moderate calorie reduction but was high in calcium. All rats supplemented with calcium showed increased body temperature, indicating a shift from calorie storage to calorie burning (as process known as thermogenesis.)
What this means is that in the presence fo calcium and vitamin D, the body turns down the volume on this fat-storing enzyme. Without adequate calcium and vitamin D available, the body turns up the volume on this fat-storing enzyme, and what you end up with is just that -a higher volume of fat working against everything an individual would like to see happen in his or her body. This is yet another reason to focus on upping calcium and vitamin D intake...to force the body to convert fat into fuel..." - Michael Holick, The Vitamin D Solution
There are, of course, numerous other benefits of being calcium replete, as an estimated 44-87% of Americans are estimated not to be.
As another responder stated, Tahini is a high O6 source.