We present a Sustainable Agroecological Farm Reproduction Analysis that links two methodologies kept separated so far: Optimization Modelling, and Social Metabolism accounting of the biophysical turnover from a fund-flow approach. This socio-agro-ecological model combines two scales, at farm-gate and municipal levels, and formalizes all relevant flows interlinking three living funds that have to be reproduced over time: the domestic unit, livestock and soil fertility. From the requirements and capacities of each fund (constraints), we run the model under different scenarios (objective functions) to see the different configurations that the landscape structure and the flow patterns can take (variables), ensuring the reproducibility of funds. By changing the objectives we obtain an intensive optimum that minimizes the land required; an extensive optimum that minimizes labour; and a monetary optimum that maximizes a prevailing cash crop. The model is applied to a past advanced organic farming of a Catalan village c.1860 to generate a set of counterfactual scenarios that, confronted with historical data, help to reveal how institutional settings and landownership inequality played a role in maintaining the real socio-agro-ecological structure away from these optima, and the existing potential of possible eco-functional intensification practices aimed at reducing the land cost of agrarian sustainability.